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Fig. 7. SEM of species lacking orbicules. A and B, Coutoubea spicata. A, General observation of a heterobrochate reticulate tetrad. B, General observation of the locule wall surface lacking orbicules. Smooth grooves (arrow) in the locule surface reveal the position of the underlying endothecial cells. C, Halenia corniculata. The locule surface possesses ridges (arrow) forming more or less a reticulum. D, Voyria caerulea. General view of a psilate 2‐porate (arrows) pollen grain.
